The metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET) is a type of transistor used for amplifying or switching electronic signals.
The MOSFET is by far the most common transistor in both digital and analog circuits, though the bipolar junction transistor was at one time much more common.
The main advantage of a MOSFET over a regular transistor is that it requires very little current to turn on (less than 1mA), while delivering a much higher current to a load (10 to 50 times or more).
PACKAGE:
TO-220
A microcontroller (i.e. Arduino) pin can source or sink only 20mA to 40mA (1 or 2 LEDs). The IRF520 can be used to drive motors and other high current devices.